Existing theories of social judgement involve information integration processes or the use of general, schematic knowledge. As an alternative, this proposal outlines a new exemplar-based model of social judgement that emphasizes the important role of the perceiver's specific past experiences. The model rests on three postulates: (1) Exemplar representations are stored in memory as they are interpreted by the perceiver and are retrieved to make social judgements, in a type of implicit memory. (2) A target stimulus serves as a cue for the retrieval of the most similar exemplars from memory. Similarity is not a fixed property of a set of stimuli, but depends on how perceivers process them, and specifically on how much attention perceivers accord to the various stimulus dimensions (Medin & Schaffer 1978). (3) A range of intrinsically social and motivational factors, including perceiver individual differences, past experiences, self-schemas, the social context, and ingroup-outgroup dynamics, have their effects on social judgement by affecting perceivers' attention to dimensions. These three postulates constitute a framework that theoretically unifies and integrates a range of known social influences on judgement by showing that they all operate through a common exemplar-based judgement mechanism. The framework also suggests testable new predictions. Eleven experiments as well as computer stimulations are proposed to further develop and test this theory. The long-term objective of this research is to increase our understanding of the social and cognitive processes involved in social judgement-- particularly effects of the perceiver's past experience and social knowledge (including stereotypes of social groups) on perceptions of and reactions to target persons and groups. Stereotypes and person perception processes are crucially important in many areas including psychiatric diagnosis, close personal relationships, and intergroup relations.